Neuroscientists and clinicians need powerful computerized data and image management resources to deal with the rising tide of new information about the brain. Such resources need to be comprehensive, accessible and capable of communicating directly with other computerized systems without the need for human intervention. Classical neuroanatomical landmarks provide an essential frame of reference for integrating new and existing information about the brain. Braininfo is a Web resource in which information is indexed by a comprehensive neuroanatomical nomenclature. The nomenclature, NeuroNames, is fully integrated with the Unified Medical Language System of the National Library of Medicine. It includes terminology for both the human and the nonhuman primate brain. Appropriate parts of the nomenclature have been incorporated into a system of neuroanatomical definitions that illustrates structural concepts by reference to an atlas of the nonhuman primate brain. We propose to create a 3-dimensional computerized atlas of the human brain and to extend this definitional system to the human brain, to establish mechanisms whereby visitors to the Brainlnfo website can map data into brain atlases on the Web, and to establish compatibility and interoperability between Brainlnfo and two of the most extensive web-based sources of data on human brain function. The resource objective of Brainlnfo and NeuroNames is to accelerate the acquisition and distribution of existing and new scientific knowledge about the brain. This will be accomplished by applying digital communications technology to enable immediate communication of information about the brain via the Web in a manner tailored to the knowledge structure and intuitive search strategies of neuroscientists, clinicians, and students of neuroanatomy. (http://braininfo.rprc.washington.edu)